Conventionally, it has been studied to use laser light in order to produce nuclear fusion in a highly controlled manner by using a small-sized and low-cost device. Further, through recent research, a great improvement in neutron production efficiency by a nuclear fusion reaction using a laser unit has been expected, and such a neutron production method using a nuclear fusion reaction has come to be expected as a safer method than by a nuclear fission reaction.
As conventional examples of nuclear fusion production methods using laser light, ones of the following non-patent document 1 and the following patent document 1 have been known. In the method described in the following patent document 1, an irradiation member prepared by coating deuterium substituted plastic on a thin film of Mylar or the like is momentarily irradiated with laser light to produce high-energy hydrogen nuclei, and a target member disposed at approximately a predetermined distance from the irradiation member is irradiated with the hydrogen nuclei to induce a nuclear fusion reaction. On the other hand, in the method described in the following non-patent document 1, two laser pulses are successively made incident at a predetermined time interval (300 psec) onto a target prepared by forming a film of deuterium substituted polyethylene (C2D4)X on an aluminum plate to induce a nuclear fusion reaction.